A linga stone placed in front of an image of Shiva
The linga is the most widely used representation of Shiva. It is simply a cylindrically shaped stone, usually placed within an alter called a yoni, meant to represent female power. The linga is thus also representative of the male aspect. In the earliest statues of the god Shiva he is almost always depicted with an erect penis. The image of the erection became synonymous with Shiva and over time it was simplified to the linga stone.
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Above the Shiva linga is treated as an image of Shiva
The linga or lingam (Sanskrit for "symbol") is the symbol of the god Shiva and the form in which he is most commonly worshipped. The phallic symbol is the main object of worship in Shaivite temples and homes throughout India and the world.
The largest linga in the world and thousands of smaller lingas at the Koti Linga Temple, Karnataka
Pancha Mukha Linga from Varanasi. Exotic India.
The linga is a simple stylized phallus that nearly always rests on pedestal of a stylized yoni, or female sex organ. Together, the linga and yoni represent the power of creative energy and fertility.
History of the Shiva Linga
Scholars believe that the linga was revered by some non-Aryan peoples of India since antiquity, and short, cylindrical pillars with rounded tops have been found in Harappan remains. The Vedic Aryans appeared to have disapproved of linga worship, but literary and artistic evidence shows that it was firmly established by the 1st–2nd century AD. The linga's form began to be conventualized during the Gupta period, so that in later periods its original phallic realism was to a considerable degree lost.
Types of Lingas
Lingas range from temporary versions made of sandalwood paste or river clay for a particular rite to more elaborate ones of wood, precious gems, metal, or stone. There are precise rules of proportion to be followed for the height, width, and curvature of the top.
Variations include the mukhalinga, with one to five faces of Shiva carved on its sides and top, and the lingodbhavamurti, a South Indian form that shows Shiva emerging out of a fiery linga to demonstrate his superiority over Vishnu and Brahma. Some lingas are topped with a cobra, symbolizing the kundalini chakra located at the base of the spine.
The most revered lingas are the svayambhuva ("self-originated") lingas, which were made directly from light without human assistance. Nearly 70 are worshipped throughout India and are places of pilgrimage.
Rituals of the Shiva Linga
In the primary religious ritual of devotees of Shiva, the linga is honored with offerings of flowers, milk, pure water, fruit, leaves and rice.
Source: http://www.religionfacts.com/hinduism/things/shiva_linga.htm
